We were planning to perform the study in two phases. In the first exploratory phase, we will conduct a short pilot study with 15 subjects to optimize and if possible simplify the treatment parameters for the second longer phase of the experiment. In this first phase we will perform one of the four different tDCS stimulation conditions concurrently with the physical therapy protocol on each therapy day, so that all subjects will receive all stimulation types in a randomized counterbalanced order. There will be a 1 day rest period in between sessions, making 9 days (10 days if initial evaluation is done on the day before the 1st treatment) the total commitment time for the first phase of study.